湖北‘天仙红’桃树流胶病病原菌鉴定

Identification of the pathogen causing‘Tianxianhong’peach tree gummosis in Hubei province

流胶病在湖北‘天仙红’桃树上发生严重。为明确引起‘天仙红’桃流胶病的病原,通过形态学、分子生物学及柯赫氏法则对采集的病害样品进行了病原菌鉴定。结果表明,获得的分离菌株JSZ01的形态学特征与小新壳梭孢Neofusicoccum parvum基本一致。BLAST比对结果显示,分离菌株JSZ01的ITS、TEF1-α和β-tubulin基因序列与N.parvum的相似性在99.2%~100%,在系统发育进化树中JSZ01与小新壳梭孢的类群处于同一分支。JSZ01接种健康桃树枝条5 d后接种部位出现溃疡流胶症状,与田间症状一致。结合形态学观察、序列分析以及致病性测定结果,将‘天仙红’桃树流胶病的病原菌鉴定为N.parvum。

Gummosis is a wide spread disease on‘Tianxianhong’peach tree in Hubei province.To identify the pathogen causing peach gummosis,the pathogenic fungus JSZ01 from the diseased twigs was isolated and purified.The morphological and molecular identification of JSZ01 was conducted.The pathogenicity of JSZ01 was confirmed according to Koch’s rule.The results indicated that the morphological characteristics of JSZ01 were in agreement with Neofusicoccum parvum.BLAST analysis showed that the rDNA-ITS,TEF1-αandβ-tubulin sequences had 99.2%to 100%identity with those of N.parvum.Phylogenetic analysis showed JSZ01 was attributed to the same branch with N.parvum in phylogenetic tree.After five days,the inoculated peach twigs exhibited necrotic lesions and secreted gum from the lesions,which were highly similar to the symptoms observed in the field.Based on the morphological characteristics,sequences analysis and pathogenicity tests,the pathogen that causing gummosis of‘Tianxianhong’peach was identified as N.parvum.